Attachment for pencil sharpeners



April 8, l930- v o. A. NARvERuD I 1,753,275

ATTACHMENT FOR PENCIL SHARPENERS Filed Oct. 11, 1926 la/ a 66' 'l nven lm Patented Apr. 8, 1930 L0]? A. NARVERUD, OF MINNEAPOLIS, MINNESOTA ATTAGHMENT ron PENCIL snnnrnnnns Application filed October 11, 1926. Serial No; 141,001.

This invention relates to a pencil sharpener and particularly to a pencil sharpener of the type driven by an electric motor, and comprises an attachment whereby the insertion of a pencil will start the motor and the re-.

moval of the pencil will act to stop the motor.

It is an object of this invention, therefore, to provide a very simple and eificient means which may be readily attached to the casing of a pencil sharpener, which is adapted to receive a pencil and start and stop the motor by the movement of the pencil.

It is more specifically an object of the invention to provide an attachment for a pencil sharpener comprising a bracket adapted to be attached to the same, having a barrel portion in alinement with the pencil receiving opening of the sharpener and having a laterally extending portion carrying one terminal of the motor and a sliding plunger connected to the other terminal adapted to be moved by the pencil to connect said terminal. 7

These andother objects and advantages of the invention will be fully set forth in the following description made in connection with the accompanying drawings, in which like reference characters refer to similar parts throughout the several views and in which Fig. 1 is a view in side elevation of a pencil sharpener and the driving shaft of the motor, said sharpener having the attachment thereon;

Fig. 2 is a view in side elevation of the device as seen from the right of Fig. 1; and

Fig. 3 is a view in vertical section taken substantially on line 3-3 of Fig. 1.

Referring to the drawings, a pencil sharp- I ener is shown, comprising a casing 1 which has the upper portion 1 containing the pencil sharpening mechanism which has an apertured hub 1 through which the pencil is inserted to be engaged by said mechanism and sharpened. The driving pulley 3 for the sharpener is shown secured to the sharpener 0 shaft 9, said pulley having a hub 10 secured 5 to said shaft 9 by the set screw 13. The shaft 4 of a driving motor is shown frictionally engaging the pulley 3, which pulley has a rubber tire 2 thereon so as to be driven by friction.

The sharpener has the usual drawer 5 in the lower portion of the casing having the handle 10 by which it is withdrawn.

In accordance with the present invention, the bracket 6 is provided which is secured to the casing 1 by a rivet 11 extending through a hub in the bottom of said bracket and through said casing. The bracket 6 also has a barrel portion 6 having an aperture therethrough alined with the hub 1 and said bracket also has a laterally extending portion 6 The latter portion has a recess'6" formed therein from which a bore orv opening extends into the barrel portion 6 A plunger 8 is provided, extending through said latter borcor opening and having a collar or enlargement 8 thereon against which bears a coiled spring 17 which surrounds said plunger, and is disposed in the recess 6. A bushing or plug 18 is threadedinto the lateral extension 6 and has a recess in one end alining with the recess 6 in which spring 17 is also disposed and against the end of which it bears. A shell 16 of insulating material is recessed at one end and threaded throughout a portion of said recess and is threaded onto the plug 18 as shown in Fig. 3, the outer diameter of the member 16 being substantially the same as the outer diameter of the laterally extending portion 6" of bracket 6.

The end of the plunger 8 extends into the recess in member 16 beyond the plug 18 and said end is slightly separated from the end of the terminal 19 forming one terminal of the motor. A cap 15 shown in Fig. 2 is adapted to fit over the end of terminal 19, and a conductor leading from this terminal to the motor is shown at 22. The other terminal for the motor is shown 20 in 2 and is connected with a binding post or terminal member 7 shown in Figs. 1 and 2.

In the operation, the parts occupy the position shown in the drawing. When the penoil is to be inserted in the sharpener to be sharpened, the tapered end thereof will be passed into the barrel portion 6 of the member 6 and as the pencil is brought into said barrel, plunger 8 will be pushed outwardly against the pressure of spring 17 and will engage the terminal 19. The motor will now be started and will turn the sharpener as long as the pencil is held in this position. After the pencil is withdrawn, spring 17 will again push the plunger to the position shown in Fig. 3, disconnecting plunger 8 and terminal 19 and thus stopping the motor. It will be understood that the other terminal of the motor to which conductor 20 is connected, will be connected with the I lunger 8 preferably through the contact 0? plug or bushing 18 which will be of brass.

From the above description it is seen that applicant has provided a very simple and eflicient attachment for a pencil sharpener and one which will operate easily and efiectively to start and stop the driving motor with the insertionof a pencil. The device can be easily applied to any commercial type ofIpencil sharpener.

t will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the parts, without departing from the scope of applicants invention, which, generally stated, consists in a device capable of carrying out the objects above set forth, in the novel parts and combinations of parts disclosed and defined in the appended claims.

What is claimed is 1. An attachment for a motor driven pencil sharpener having an opening in which the encil is inserted to be sharpened, comprismg a bracket having a barrel portion, an arm extending from said barrel portion having an apertured lug, means extending through said lug for attaching said bracket to said sharpener, said bracket having a portion extending laterally from said barrel portion, a

plunger slidably mounted in said portion and connected to one terminal of the motor, a member disposed in said portion and connected to the other terminal of the motor and spaced slightly from said plunger, a coiled spring disposed in said portion normally holding said plunger in position spaced from said last mentioned member,

said plunger projecting into said barrel whereby when a pencil is inserted in said barrel said plunger will be moved longitudinally and will engage said last mentioned member to close the motor circuit and start the motor and said circuit will be opened when said pencil is withdrawn.

2. An attachment for a motor driven pencil sharpener, having an opening in which the pencil is inserted to be sharpened, comprising a bracket having a lug adapted to be attached to the casing of said sharpenerhaving a barrel portion adapted to be alined with said opening and having a laterally projecting portion extending from said barbushing inserted through said portion and having a recess alining with the recess in said portion, a plunger slidably mounted in said bushing and having one end projecting into said barrel, a spring disposed in said recess for holding said plunger in said position, said plunger being connected to one terminal of said motor, a shell threaded onto said bushing and disposed against said portion, a terminal member carried in said shell and connected to the other terminal of the motor, said terminal being separated slightly from said plunger whereby when a pencil is inserted in said barrel, said plunger will be retracted and will engage said terminal, thus closing the motor circuit and starting the motor and sharpener.

OLOF A. NARVERUD.

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